COVID-19 update in Maryland, US

(Updated: 2020-04-19 21:10:45 EDT)

So, I have been watching the epidemic in China and Korea since the beginning, but it is still not easy to settle into this reality here in the US.

  • First of all, everyone, STAY HEALTHY and see what YOU can do!

  • Second, there are many excellent news articles and information sources, but I’m sharing some more questions (see left panel) and answers for those who are curious about a specific situation in Maryland, US - especially including local data. Maryland is my beautiful adopted home state of over 20 years. The State is doing its best with strong leadership, but this virus arrived here when the country was not ready and is spreading fast unfortunately…

See footnote for further information about data sources. More questions and answers will be added, as more local data become available.

(Sorry, this is not mobile device friendly, and is best viewed on your regular monitor.)


Q 6. How has it affected population across different races? (NEW)

The Maryland Department of Health started publishing data by race (i.e., the number of cases and deaths by race) on April 9th, following an upsetting report about racial disparity in COVID mortality in the US: higher morality in states with higher proportions of black population. Further data - specifically disaggregated by individual people’s race, beyond the state-level analysis - are crucial to monitor and understand the disparity. Also, though initially unavailable, a separate category for Hispanic popualtion is published on April 15. As a resident of Maryland, I am very proud of the state’s rapid action to publish race data!

However, note that 20 % of cases do not have race information (i.e., “missing” race). This is likely because private labs are not required to report race.

Hover over each figure to see values and more options.

Now with Hispanic population disaggregated from “other”, the pattern of incidence and mortality by race/ethnicity can be examined better. In terms of rates, incidence is substantially higher among Other, African American, and Hispanic population (blue bars). Currently, mortality rate is highest among White and Asian Americans (orange bars). This implies that the disproportionately higher number of deaths among African American population in Maryland is because of the higher rate of infection among African Americans, not because of higher risk of dying among those African Americans who are infected. At the same time, though the infection rate is lower, mortality risk is higher among Asian Americans in Maryland.

To understand reasons behind this, we will need to learn more about characteristics of patients by race (e.g., Do Asian Americans with COVID tend to be older and/or have existing conditions in Maryland?) and any differences in access to health care by race among COVID patients. Also, what can we do to reduce the higher infection rate among African Americans and Hispanic population in Maryland? Finally and importantly, if and when we have better data on race (i.e., less cases with missing race information), the findings on racial disparity can change.

(Note: In Maryland, “Other” population includes: American Indian and Alaska Native, Native Hawaiian and Other Pacific Islander, and ‘Two or more races’. It accounts for about 3% of total population in the state.)

Hover over each figure to see values and more options.

(Source: Maryland Department of Health’s Maryland COVID-19 Case Map Dashboard, and Maryland Department of Planning’s Population Estimates by Race and Hispanic Origin for July 1, 2018)

Q 5. What is the latest mortality, and how has it changed?

As of 2020-04-19 10:00AM, 486 COVID-19-positive deaths have occurred, according to Maryland Department of Health. This means 3.8 percent of all confirmed cases. Below figure shows mortality by county - in terms of both absolute number (blue bars) and rate (orange bars) as of 2020-04-18.

(Source: New York Times’ Coronavirus in the U.S.: Latest Map and Case Count, US Census Bureau’s County Population Totals: 2010-2019)

Below chart shows the mortality trends, since March 18 when the first COVID-19 death was reported in Maryland. In countries severely affected by the epidemic before US, mortality rates increased rapidly in the beginning. Mortality rates then stabilized in some of the countries, depending on health systems’ response.

(Source: New York Times’ Coronavirus in the U.S.: Latest Map and Case Count, US Census Bureau’s County Population Totals: 2010-2019)

Q 4. How extensive has testing been?

This is a very important question, since the magnitude of testing over time is critical information to understand the epidemic. Unfortunately, I haven’t found good trend data on testing in Maryland, and decided to track COVID-19 Case Map Dashboard by Maryland Department of Health starting from March 31, 2020. However, I would apprecite very much if anyone can share testing trend data in Maryland!.

As of 2020-04-19 10:00AM, a total of 67891 tests have been conducted. There are about 6 million people in Maryland, and this means 11.2 tests have been conducted in every 1000 people. Below shows the number of new tests by date in Maryland - well, only starting from March 31st.

A large spike on the number of new tests on April 7th appears to be artifact of delayed processes in laboratory and/or data entry, not actual changes in the number of tests.

(Source: Maryland Department of Health’s Maryland COVID-19 Case Map Dashboard)

Q 3. What age groups are affected?

COVID-19 has affected adult population relatively evenly across different ages (above 200 per 100,000 population in all age groups 30 and above). Recently, however, the incidence rate has increased more rapidly among those 80 and older. Currently, the incidence rate is highest, 440 per 100,000 population, among people 80+ years of age.

(Source: Maryland Department of Health’s Maryland COVID-19 Case Map Dashboard, and Maryland Department of Planning’s Population Estimates by Race and Hispanic Origin for July 1, 2018)

Q 2. How fast has it been spreading? (NEW FIGURE ADDED)

Since testing capacity has been low, we cannot confidently answer this question. Nevertheless, we can see the number of NEW confirmed cases each day. The first figure is for the entire state. We want to see the number of new infections to be stable more or less, without sudden and large increases. On 2020-04-18, 736 new cases were confirmed, compared to 788 on the previous date. The (now relatively small) peak on March 28th was due to new cases in Carroll county on March 28 - see the second figure below.

The spike of new cofirmed cases on April 8th may be artifact of delayed processes in laboratory and/or data entry, not an actual increase on this speciic date.

Hover over each figure to see values and more options.

(Source: New York Times’ Coronavirus in the U.S.: Latest Map and Case Count)

Now, among 15 counties with 50 or more confirmed cases, below shows the trends of daily number of NEW confirmed cases for each of the county. The number of new cases surged in Carroll county on March 28th, because of an outbreak at a nursing home.

Hover over each figure to see values and more options.

(Source: New York Times’ Coronavirus in the U.S.: Latest Map and Case Count)

And, below detailed figure is for 10 counties with 150 or more confirmed cases.

Again, large spikes on April 7th may well be results of delayed processes in laboratory and/or data entry, not actual increases on that date.

Hover over each figure to see values and more options.

(Source: New York Times’ Coronavirus in the U.S.: Latest Map and Case Count)

Q 1. How many confirmed cases do we have now, and where are they?

As of 2020-04-19 10:00AM, 12830 confirmed cases have been reported in Maryland, according to Maryland Department of Health. This means there are 212 people with confirmed COVID-19 per 100,000 population in the state.

Below figure shows number of confirmed cases by county by the end of 2020-04-18.

Hover over each figure to see values and more options.

(Source: New York Times’ Coronavirus in the U.S.: Latest Map and Case Count)

When we look at infection rates (i.e., number of confirmed cases per 100,000 population), Prince George’s county now has the highest rate currently.

Hover over each figure to see values and more options.

(Source: New York Times’ Coronavirus in the U.S.: Latest Map and Case Count, US Census Bureau’s County Population Totals: 2010-2019)


Data sources:
1. All COVID-19 data for counties come from New York Times’ Coronavirus in the U.S.: Latest Map and Case Count. Accessed on 2020-04-20.
2. All COVID-19 data for Maryland disaggregated by age and sex come from Maryland COVID-19 Case Map Dashboard by Maryland Department of Health. This dashboard presents latest numbers as of 10:00AM on each day. Accessed on 2020-04-20.
3. All data on county population come from US Census Bureau’s County Population Totals: 2010-2019. Accessed on March 29, 2020.
4. Data on Maryland population by age and sex come from Maryland Department of Planning’s Population Estimates by Race and Hispanic Origin for July 1, 2018. Accessed on April 1, 2020.


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